Learn
Recreate Graphs using Matplotlib!
Stacked Bars

Now, we are going to look at the chart called `stacked-bars.png`. This graph displays the breakdown of students who got As, Bs, Cs, Ds, and Fs in each unit. The data you will need to recreate this chart is in the lists `As`, `Bs`, `Cs`, `Ds`, `Fs`, and `unit_topics`.

Save your recreated chart to a file called `my_stacked_bar.png`.

### Instructions

1.

The `Bs` bars will go on top of the `As` bars, but at what heights will the `Cs`, `Ds`, and `Fs` bars start?

The bottom of the bars representing the `Cs` will be at the height of the `As` plus the `Bs`. We can do this in NumPy (a scientific computing package for Python) with the `np.add` function. `c_bottom`, the starting heights for the `Cs`, will be:

``c_bottom = np.add(As, Bs)``

Underneath the definition of `c_bottom`, define `d_bottom` (where the `Cs` end), and `f_bottom` (where the `Ds` end).

2.

Create a figure of width `10` and height `8`.

3.

Plot the `As`, `Bs`, `Cs`, `Ds`, and `Fs`. Give each one the appropriate `bottom` list that will stack them on top of each other.

4.

Create a set of axes and save them to `ax`.

5.

Set the x-ticks to be `range(len(unit_topics))`.

6.

Set the x-tick labels to be the `unit_topics`.

7.

Give the plot the title you see in the final graph, and the same x-axis label and y-axis label.

8.

Save your figure to a file called `my_stacked_bar.png`.